1. Field of the Invention
The present disclosure relates to a cluster system and a power management method thereof, and more particularly, to a cluster system, which can reduce power consumption by controlling power under a cluster level according to the load of the cluster system, and a power management method of the cluster system.
2. Description of the Related Art
Various attempts have been made to reduce the power consumption of a computer system that consumes a large amount of power. A basic principle of reducing the power consumption of a computer system is to switch currently unused components into a low power mode. On the other hand, the basic principle is to switch the components into a normal operation mode when they start to operate, to thereby carry out an original task. It is an advanced configuration and power interface (ACPI) to have standardized such a power management scheme.
The ACPI is a power management specification that is co-developed by Intel, Microsoft, and Toshiba Inc, and can turn off power supplied to the currently unused components by allowing it to control a power connected to the components of a computer. For this end, the ACPI defines various power states with respect to each computer component, and provides an interface capable of changing the power state of each component according to the state of a computer. An operating system (OS) or an application program uses the ACPI to control the power consumed in each component. In this case, an algorithm for determining when to switch each component into the low power mode or the normal operation mode is independently determined by the OS or the application program.
A dynamic voltage scaling (DVS) is a technology that reduces the power consumption of the CPU, which is the most power consuming component in the components of a computer. More specifically, the DVS can reduce the power consumption of the CPU by controlling the operation frequency and the voltage of the CPU. Since the CPU operates in synchronization with a clock, the CPU has characteristics that its power consumption is reduced in slowing down its operation frequency. Further, power consumption is in proportion to the square of a voltage, thus the consumption of power is reduced in lowering the voltage.
Various technologies for the power consumption reduction have been introduced, but they manage power of local hardware resources at an individual node level. Accordingly, power is not effectively managed in view of an entire cluster system. However, the cluster system in which nodes are connected to one another requires a cluster level power management.
Since all nodes in a typical cluster system are always operated in the maximum performance mode, the typical cluster system has a disadvantage in that power is consumed even when the cluster system does not operate.